The line of Hesse-Cassel was founded by William IV., surnamed the.Wise, eldest son of Philip the Magnanimous. On his father’s death in 1567 he received one half of Hesse, with Cassel as his capital; and this formed the landgraviate of Hesse-Cassel. Additions were made to it by inheritance from his brother’s possessions, while, as compensation for losses sustained in the Thirty Years’ War, a large part of the countship of Schaumburg and other territory was acquired towards the middle of the 17th century. Charles I., who ascended the throne in 1670, was the first ruler who adopted the system of hiring his soldiers out to foreign powers as mercenaries, as a means of improving the national finances. Frederick I., the next landgrave, had become by marriage king of Sweden, and on his death was succeeded in the landgraviate by his brother William VIII., who fought as an ally of England during the Seven Years’War. From , his successor Frederick II., v ’ ho had become a Roman Catholic, 22,000 Hessian troops were hired by England for about £3,191,000, to assist in the war against the North American colonies. The reign of the next landgrave, William IX., was an important epoch in the history of Hesse-Cassel. Ascending the throne in 1785, he took part in the war against France a few years later, but in 1795 peace was arranged by the treaty of Basel. For the loss in 1801 of his possessions on the left bank of the Rhine he was in 1803 compensated by some of the former French territory round Mainz, and at the same time was raised to the dignity of Kurfürst or Elector William I. In 1806 he made a treaty of neutrality with Napoleon, but after the battle of Jena the latter, suspecting William’s designs, occupied his country, and expelled him. Hesse-Cassel was then added to Jerome Bonaparte’s new kingdom of Westphalia; but after the battle of Leipsic in 1813 the French were driven out and the elector restored. By the Vienna congress, where he intrigued in vain to be recognized as a king, several changes in the extent of his dominion were made. On his return to his sovereignty, William promised to grant his people a new and popular constitution; but just as the draft was ready to become law by his signature, he drew back, dissolved the diet, and continued to rule without again summoning it. His son, William II., who succeeded in 1821, pursued the same line of policy, and carried on the government without reference to the diet. The discontent which this conduct excited was intensified by the elector’s shameless connexion with the countess of Reichenbach. Disturbances took place, and the elector, after attempting to pacify his people, appointed his son as regent in 1831, and withdrew to Frankfort, where he died in 1847. The regent, becoming Elector Frederick William I., startled by the Paris revolution of 1848, made many promises to the people, and carried some of them into effect, but on the reaction of 1850, which spread over all Germany, snatched at the first pretext for returning to the former order of things. He attempted to levy the usual taxes without obtaining the consent of his chambers, but the commotion thus caused was so great that he was forced to retire to Wilhelmsbad, along with his very unpopular minister, Hassenpflug. He induced the diet of princes then assembled at Frankfort to support him, and Austrian and Bavarian troops entered Hesse-Cassel to enforce obedience. Prussia, iu alarm, immediately occupied the northern part of the country, and a civil war was barely avoided by arrangement. The elector, however, scarcely changed his policy, and the next sixteen years were occupied with disputes between the chambers and the Government. In 1866 Hesse-Cassel joined Austria against Prussia. Prussian troops immediately overran the country, and on the treaty with Austria, the electorate was annexed to the Prussian kingdom. The elector was carried a prisoner to Stettin, and was only released on resigning his claims to the throne of Hesse-Cassel. He died in 1875.

See Wippermann, Kurhessen seit den Freiheitskriegen, 1850; Röth, Geschichte von Hessen-Kassel, 1856; Gräfe, Der Verfassungskampf in Kurhessen, 1851; and works under Hesse.